Can I "test out" cloth diapering first?

It's difficult to "try out" cloth diapering because it's a large initial investment that pays for itself within 6 months. With that said, I can think of a few economical ways you might get your feet wet before jumping in:

1) Craigslist. I know. Gross.  But. Here's a secret.  Diapers have excellent resale value.  They often sell for 70% of their initial value.  Check online.  Check on craigslist. This is good news for you when you want to sell off your stash.  It also means that there are great deals to be had.  I scored 11 diapers for $55 off of Craigslist from a sweet little Indian family that was moving back to India.  These diapers had been used for 3 years and were still kickin'. It allowed me to pilot my cloth diapering program with Chandler before Ellie arrived. It also allowed me to see the downside to velcro and the upside of snaps since the velcro was in rough shape and a major pain in the butt, but the lone snaps diaper looked good as new.

OR

2) Buy prefolds and covers -  Get a pack of prefolds (I highly recommend GMD Cloth-eez) and a few Thirsties snap covers (adjustable).  You can sometimes score some "irregular" diapers from the website that are marked down considerably but work just as well.  I got a dozen large size for $24 that way.  Covers are about $13 each but you can usually score cheaper ones by looking at the "open box" option on Amazon or the "seconds" section of cloth diapering websites.  This will allow you to determine if cloth diapering is for you. As a caveat, however, prefolds are a bit more cumbersome than pocket diapers.  The good news? If you don't mind prefolds, pocket diapers will be a breeze.  I personally love prefolds, and still use them often with Ellie even though she easily fits in the pocket diapers.

OR

3) Buy Alvababy diapers from China.  I recommend the $6.99 double gusset color snap because those are the most like BumGenius.  I own their $4 and $5 diaper but those do leak at times.  If you want to stock up on 7-8 of the Alvababy double gusset first (rather than the 3x  more $$ Bumgenius), you can get an idea of whether or not this is for you.  If you don't like them, resell them and recoup some of those costs.

*Don't buy a diaper pail and liner while you are testing it out.  Just dedicate small trashcan with a grocery bag and dump the small load of diapers in and toss the shopping bag in the trash. 

*Pick up a small box of Tide Ultra Powder detergent.  Just use 1 to 1 1/2 TBSP for each load.

If you decide it's for you, then go forth and get the good stuff. You will still save major money in the end.  I started off with the tiny trashcan in the garage and the Craigslist diapers.  But once I knew this was going to work for me, I bought the Charlie's soap, pocket diapers, hemp inserts, and pail liners so that life would be easy.  I love cloth diapering.  Every time I am running low on diapers, I just do a load of laundry.  It's kind of like magic.